get_org

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds a meaningful behavioral constraint: 'The tax id is returned only as `einLast4`; a full EIN never leaves the server,' which is not visible in the schema or annotations. This gives the agent a hard expectation about data availability.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three compact sentences front-load the purpose, then give routing guidance, then state a data-availability caveat. There is no filler or repetition of schema fields.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given a single parameter, a rich input schema, a full output schema, and annotations covering read-only and idempotent behavior, the description supplies the only remaining context: which data source to use and the EIN truncation rule. Nothing an agent needs to invoke this tool correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, and the `entity` parameter is already documented as requiring the exact `entity` key from `list_entities`, not `display_name`. The description reinforces the key-vs-display-name distinction but does not add new parameter semantics beyond the schema. A baseline 3 is appropriate because the schema carries the burden.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with 'Organization profile:' and enumerates the exact fields returned (legal name, DBAs, kind, subscription tier, billing cadence), making the resource and scope clear. It also distinguishes itself from list_entities by saying it is used for legal name, DBAs, and EIN last four, whereas list_entities provides entity keys and display names. This is specific and immediately disambiguates the tool from its siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives an explicit directive: 'Use this for the legal name, DBAs, and EIN last four Mercury holds; use `list_entities` for entity keys and display names...' This names the alternative and states the split of responsibilities. No agent needs to infer when to call this tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.